Blue on blue is normally a military term. Military discipline is one thing sorely lacking in the Conservative Party at the moment.

It may have been the toughest decision of Michael Gove’s life, but his support for a vote to leave the EU could cost him his job. This weekend’s fevered speculation includes a post-referendum “revenge reshuffle”.

This pre-supposes a couple of things. Firstly, a vote to stay in the EU. Secondly, David Cameron’s willingness to provoke an full-on civil war in his party.

Iain Duncan-Smith is apparently already considering life on the back-benches, telling the Telegraph "If my face no longer fits, my face no longer fits", while Boris Johnson has gambled it’s worth losing out on a top job like Foreign Secretary to win the hearts of Eurosceptic Tory MPs — who will choose the leadership candidates put to Tory members whenever Mr Cameron steps down.

While the In camp talk of a purge of Outers, those campaigning for exit talk of leadership challenges to the Prime Minister, regardless of the referendum result. With more than a-hundred Tory MPs apparently settled on campaigning to leave, it’s unlikely to be a struggle find the numbers needed to force a vote. That doesn’t necessarily mean it’s a good idea.

Of course, it wouldn’t be the first time the Conservatives have chosen to publicly disembowel themselves over Europe. No doubt many Tories are desperate to avoid this, and watch with dismay as rival factions hurl grenades at each other. Some have resorted to loudly shouting that there’s nothing to see here, in a faintly ridiculous attempt to deny the blindingly obvious.

It’s true to say that the battles inside the Conservative Party are not the key issue in the EU referendum campaign. But they still matter — the Tories have to govern for a further four years once this referendum is over, and right now it’s hard to see them uniting behind David Cameron or, frankly, anyone else.

Europe has always been the Tories’ most toxic issue — and even this “once in a generation” vote seems unlikely to draw out all the poison.

Meanwhile, where on earth is Jeremy Corbyn in all this?

On paper, the Labour leader supports staying in the EU — but he seems unwilling to go beyond tepid support.

Alan Johnson will be the face of Labour’s campaign, struggling to make himself heard above the Tory squabbling.

There are other voices in this debate, beyond the yelling from either side of the Tory divide — hopefully at some stage we may even get to hear them.